class FC:
    pass

a = FC()

a.one = 1
a.ten = 10 
 
print (a.ten - a.one)

class FC:
    one = 1
    ten = 10

a = FC.one
b = FC.ten 
 
print (b - a)

class FC:
    def __init__(self,one,ten):
        self.one = one
        self.ten = ten

 a = FC(1,10)

class FC:
    def __init__(self,one,ten):
        self.one = one
        self.ten = ten
    def show(self):
        print (self.ten,"-",self.one,"=",self.ten - self.one)

a = FC(one=1,ten=10)

a.show()